Field of the Invention
The embodiments disclosed herein relate generally to fuel systems for an any internal combustion engines and more particularly to a fuel conditioning and injection system employing a volume in contact with combustion temperatures for adiabatic heating of fuel pumped into the chamber at a fuel rail pressure to high pressure and temperature and conversion of at least a portion of the fuel into more highly energized radical molecules for self-injection through open orifices into the combustion chamber of the engine. The open orifices allow partial oxidation of the fuel charge during adiabatic heating for formation of radicals improving combustion performance.
References to Related Art
Internal combustion engines, and more particularly compression-ignition engines, also known as a Diesel cycle engines, perform at maximum output and efficiency when the maximum combustion pressure occurs in a desired rotation range of the engine crank shaft somewhere between 20 and 30 degrees after top dead center (TDC) down in the working cycle. There is a measurable time lag between the point of fuel injection into the combustion chamber and combustion occurring, which is known as ignition delay. Fuel must be injected earlier to have time to ignite and combust developing maximum pressure at the desired rotation range. In most compression-ignition engines the fuel is injected into combustion chamber and starts raising pressure in the combustion chamber before the engine has completed the compression cycle, which is necessary to obtain the peak combustion pressure in the desired rotation range. This negatively affects life of the engine due to overloading and also produces noise known as “knock”. In these engines, if fuel was injected after the compression cycle to eliminate the knock, then maximum combustion pressure will develop at greater than the desired 20-30 degrees of working cycle of the crank shaft, wasting combustion energy through the exhaust cycle and resulting in output and efficiency losses. Alternatively, the engine can be switched to a different fuel quality or cetane number to reduce ignition delay.
It is known in the prior art that compression-ignition engines working on gasoline are far more efficient compared to gasoline powered Otto cycle engines. However, such engines produce a power output only about 75% of an Otto cycle engine of equal displacement. Prior art compression-ignition engines do not provide homogeneous mixture of fuel with oxidizing atmosphere prior to combustion, and the greater amount of fuel after a certain level being injected into the engine creates incomplete fuel burn, resulting in unacceptable emission levels.
It is also known that higher efficiency can be obtained by conditioning fuel to a high energy state prior to introduction into the combustion chamber of the engine, and more particularly preheating, pressurizing and partially oxidizing the fuel to a vapor and above a critical state with an optimal ratio of fuel molecules in radical formation. It has been well established that only molecules in radical formation ignite and combust and that ignition delay is the time interval between introduction of the fuel into an oxidizing atmosphere, fuel transformation in several states to form radicals and initial oxidation of the radicals that is combustion. Parameters affecting transformation of the fuel molecules to formation of the radicals are heating the fuel to the temperature exceeding 1000 F. with initial pressure applied, or heating the fuel molecules above critical temperature and critical pressure for particular type of fuel with partially oxidation. The ignition and following combustion occurring from oxidizing fuel radicals in high concentration of oxygen constituting the combustion event is independent from the temperature of the oxidizer. Somewhat different from pure compression-ignition engines, this type of engine operation is called injection-ignition. It has also been found that radicals have four times higher ability to mix with oxidizer, providing a more homogeneous mixture and providing ability to increase power density of an engine.
It is therefore desirable to provide a conditioner and injector system for engines to have a negligible ignition delay where fuel can be injected after the compression cycle with combustion maximum pressure reached between 20 and 30 degrees after piston TDC down in the working cycle main operating shaft rotation with the engine performing at a maximum efficiency without knock. It is also desirable to provide a greater power density of the compression-ignition engines, for a particular engine displacement with any desired type of fuel and that engine displacement can be reduced with engine output requirements leading to reduce fuel consumption, reduced engine dimensions and weight thereby lowering manufacturing cost. It is also advantageous for the engine to have homogeneous mixture of fuel with oxidizing atmosphere prior combustion. It is still further advantageous for the conditioner and injector system to introduce fuel into the combustion chamber of the engine above critical state with an optimum level of radicals, instead of a liquid form at an engine environmental temperatures, thereby providing a greatly reduction ignition delay and increasing thermal efficiency of the combustion.